-----Original Message-----
From: David Robley [mailto:robleyd@;paradise.net.nz]
I'm going to stick my neck out here - as I understand it, this is not an
omission in php, rather it is a restriction of the underlying OS/file
system. <Extends neck more> To the best of my knowledge, neither the FAT
based system of M$DOS or e2fs under *nix will allow random access _to the
contents of a specific file_ without the need to read/rewrite the
entire file. Is there in fact any file system that allows this?
----
All of the file systems I have ever worked with over the last 25 years allow
random read/writes (via calls similar to fseek() ); however, random writes
involve fixed-length blocks if you want to re-write in place. PHPs fseek()
will allow you to do random read/writes on fixed length blocks just like the
underlying C call.

Variable length blocks (say, those ending in random new lines) are by
definition non-deterministic; therefore re-writes in place are impossible
without OS help in inter-block jumps/relinks and the subsequent waste of
file space. The Pick O/S from a long time back allowed something like this
if I remember right (Pick Systems is now RainingData markets a high-end
database)  .

Mark C.


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